Composite integrated semiconductor device

ABSTRACT

A composite integrated semiconductor device. In one embodiment, an input surge/noise absorbing circuit absorbs surge from an input signal, an attenuating circuit attenuates the input signal, and an electrical signal converting circuit converts the input signal to an output signal. The input surge/noise absorbing circuit, the attenuating circuit, and the electrical signal converting circuit together form a unit, and a plurality of these units are arranged in parallel in one semiconductor substrate to form the composite integrated semiconductor device, resulting in a reduction in the number of discrete components mounted on a printed circuit board.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No. 11/723,356, filed Mar. 19, 2007, now allowed, which is a continuation of U.S. application Ser. No. 10/235,841, filed Sep. 6, 2002, and now abandoned and which further claims the benefit of priority of Japanese Patent Application No. 2001-269773 filed Sep. 6, 2001, the contents of which are incorporated herein by reference. This application is also related to JP 2002-164890 filed Jun. 5, 2002, the contents of which are incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a composite integrated semiconductor device in which there are integrated on the same semiconductor substrate different circuits such as an input surge/noise absorbing circuit for absorbing surge or noise, an attenuating/level-shifting circuit providing attenuation or level-shifting operations, and an electrical signal converting circuit providing an electrical signal converting operation. In particular, the present invention relates to a composite integrated semiconductor device that inputs a signal without surge and noise to a control unit controlling, for example, the electrical equipment of an automobile, with the electric potential level of the signal being matched to the electric potential level of the control unit.

2. Description of the Related Art

Conventionally, circuits such as a surge/noise absorbing circuit for absorbing surge or noise, an attenuating/level-shifting circuit providing an attenuating or a level-shifting operation, an electrical signal converting circuit providing an electrical signal converting operation, etc., are connected to an input side of an electrical control unit (ECU) that controls the electrical equipment of, for example, an automobile. These circuits permit the inputting of a signal without surge and noise, with an electric potential level of the signal matched to an electric potential level of the control unit. FIG. 16 is a block diagram schematically showing a conventional configuration of these functional circuits.

As shown in FIG. 16, a plurality of discrete components 1 such as resistors, capacitors, and diodes are combined, as required, and mounted on a printed circuit board (not shown). External electrical input signals 2 are supplied through the discrete components 1 forming the functional circuits and output as electrical output signals 3, which are supplied to the input terminals 5 of a semiconductor device 4 without surges and noise. Each of the signals is matched to a driving electric potential level of the semiconductor device 4.

In the conventional configuration as described above, however, realization of the circuits having the desired functions has been achieved using a large number of the discrete components 1. This has resulted in an increase in the mounting area of a printed circuit board, and an associated increase in the number of man-hours required to mount the components.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a composite integrated semiconductor device in which the number of components mounted on a printed circuit board is reduced, decreasing the mounting area on the printed circuit board and the number of man-hours required to mount the components.

The above object can be attained by a composite integrated semiconductor device in which circuits such as an input surge/noise absorbing circuit, an attenuating/level-shifting circuit, and an electrical signal converting circuit are integrated in the same semiconductor substrate.

According to one aspect of the present invention, a composite integrated semiconductor device comprises a plurality of inputting devices, such as input terminals, receiving external electrical signals, a plurality of outputting devices, such as output terminals, for outputting electrical signals, and a plurality of input surge/noise absorbing circuits absorbing surges or noise. Each of the input surge/noise absorbing circuits is connected between one of the inputting devices and a corresponding outputting device. The semiconductor components forming the input surge/noise absorbing circuits are integrated in the same semiconductor substrate.

In another aspect of the present invention, a composite integrated semiconductor device comprises a plurality of inputting devices, such as input terminals, receiving external electrical signals, a plurality of outputting devices, such as output terminals, outputting electrical signals, and a plurality of attenuating circuits providing an attenuating operation. Each of the attenuating circuits is connected between one of the inputting devices and a corresponding outputting device. The semiconductor components forming the attenuating circuits are integrated in the same semiconductor substrate.

In a further aspect of the present invention, a composite integrated semiconductor device comprises a plurality of inputting devices, such as input terminals, receiving external electrical signals, a plurality of outputting devices, such as output terminals, outputting electrical signals, and a plurality of electrical signal converting circuits providing an electrical signal converting operation. Each of the electrical signal converting circuits is connected between one of the inputting devices and a corresponding outputting device. The semiconductor components forming the electrical signal converting circuits are integrated in the same semiconductor substrate.

In a further aspect of the present invention, a composite integrated semiconductor device comprises a plurality of inputting devices, such as input terminals, receiving external electrical signals, and a plurality of outputting devices, such as output terminals, outputting electrical signals. Each of a plurality of input surge/noise absorbing circuits absorbing surges or noise is connected between one of the inputting devices and a corresponding outputting device. A plurality of attenuating circuits provide an attenuating operation. Each of the attenuating circuits is connected between one of the inputting devices and a corresponding outputting device. The semiconductor components forming the input surge/noise absorbing circuits and the semiconductor components forming the attenuating circuits are integrated in the same semiconductor substrate.

In a further aspect of the present invention, a composite integrated semiconductor device comprises a plurality of inputting devices that receive an input electrical signal, a plurality of outputting devices that transmit an output electrical signal, a plurality of input surge/noise absorbing circuits that absorb surge or noise of the input electrical signal, and a plurality of electrical signal converting circuits that convert the input electrical signal to the output electrical signal. Each of the input surge/noise absorbing circuits is connected between respective ones of the inputting devices and corresponding outputting devices. Also, each of the electrical signal converting circuits is connected between respective ones of the inputting devices and corresponding outputting devices. A plurality of semiconductor components form the input surge/noise absorbing circuits and the electrical signal converting circuits and are integrated in the same semiconductor substrate.

In a further aspect of the present invention, a composite integrated semiconductor device comprises a plurality of inputting devices that receive an input electrical signal, a plurality of outputting devices that transmit an output electrical signal, a plurality of attenuating circuits that attenuate the input electrical signal, and a plurality of electrical signal converting circuits that convert the input electrical signal to the output electrical signal. Each of the attenuating circuits is connected between respective ones of the inputting devices and corresponding outputting devices. Also, each of the electrical signal converting circuits is connected between respective ones of the inputting devices and corresponding outputting devices. A plurality of semiconductor components form the attenuating circuits and the electrical signal converting circuits and are integrated in the same semiconductor substrate.

In a further aspect of the present invention, a composite integrated semiconductor device comprises a plurality of inputting devices that receive an input electrical signal, a plurality of outputting devices that transmit an output electrical signal, a plurality of input surge/noise absorbing circuits that absorb surge or noise of the input electrical signal, a plurality of attenuating circuits that attenuate the input electrical signal, and a plurality of electrical signal converting circuits that convert the input electrical signal to the output electrical signal. Each of the input surge/noise absorbing circuits, the attenuating circuits, and the electrical signal converting circuits is connected between respective ones of the inputting devices and corresponding outputting devices. A plurality of semiconductor components form the input surge/noise absorbing circuits, the attenuating, and the electrical signal converting circuits, and are integrated in the same semiconductor substrate.

In a further aspect of the present invention, a composite integrated semiconductor device comprises inputting means for inputting an input electrical signal, outputting means for outputting an output electrical signal, input surge/noise absorbing means for absorbing surge or noise of the input electrical signal, and being connected between the inputting means and the outputting means, the input surge/noise absorbing means including a first diode being connected between a power source line and the inputting means and a second diode being connected between the power source line and a ground, and attenuating circuits for attenuating the input electrical signal, and being connected between the inputting means and the outputting means. A plurality of integrated circuits are formed, with each of the plurality of integrated circuits including an input surge/noise absorbing means and an attenuating circuit, and each of the plurality of integrated circuits being integrated in an n type semiconductor substrate. The input surge/noise absorbing means includes at least two vertical type diodes, an anode of one of the at least two vertical type diodes being connected to the inputting means, and an anode of another of one of the at least two vertical type diodes being connected to the ground. The n type semiconductor substrate is connected to the power source line.

In a further aspect of the present invention, a composite integrated semiconductor device comprises inputting means for inputting an input electrical signal, outputting means for outputting an output electrical signal, input surge/noise absorbing means for absorbing surge or noise of the input electrical signal, and being connected between the inputting means and the outputting means, the input surge/noise absorbing means including a first diode being connected between a power source line and the inputting means and a second diode being connected between the power source line and a ground, attenuating circuits for attenuating the input electrical signal, and being connected between the inputting means and the outputting means, and electrical signal converting means for converting the input electrical signal to the output electrical signal, and being connected between the inputting means and the outputting means. A plurality of integrated circuits are formed, with each of the plurality of integrated circuits including an input surge/noise absorbing means and an attenuating circuit, and each of the plurality of integrated circuits being integrated in an n type semiconductor substrate. The surge/noise absorbing means, attenuating circuits, and electrical signal converting means are connected in sequence toward the outputting means from the inputting means between the inputting means and the outputting means. The plurality of input surge/noise absorbing means includes at least two vertical type diodes, an anode of one of the at least two vertical type diodes being connected to the inputting means, and an anode of another of one of the at least two vertical type diodes being connected to the ground. The n type semiconductor substrate is connected to the power source line.

In each of the aspects described above, the input surge/noise absorbing circuits are able to withstand an electrostatic surge of approximately ±0.5 kV to 15 kV or more at approximately 150 pF and 500Ω, or an electrostatic surge of approximately ±1000V or more at approximately 100 pF and 1500Ω, or an electromagnetic wave noise of approximately 20 to 100 V/m or more at approximately 10 kHz to 200 MHz. Also, the composite integrated semiconductor device according to the preferred embodiment of the present invention may output the electrical signals through the outputting devices to a controller controlling the electrical equipment of an automobile, for example. The position of the outputting devices may form an angle of about 90° or more with respect to the position of the inputting devices. In addition, the semiconductor substrate on which all the semiconductor components are integrated may be sealed using a resin or ceramic.

In each of the aspects describe above, the input surge/noise absorbing circuits, the attenuating circuits, and the electrical signal converting circuits are integrated on the same semiconductor substrate. This reduces the number of components mounted on a printed circuit board compared with a conventional circuit configuration in which semiconductor devices having discrete components are combined.

These together with other aspects and advantages that will be subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an example of the configuration of a composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 2 is a block diagram schematically showing an example of an interface between the composite integrated semiconductor device of FIG. 1 and another semiconductor device.

FIG. 3 is a plan view of a chip showing an example of a chip layout of the composite integrated semiconductor device of FIG. 1.

FIG. 4 is a block diagram showing another example of a configuration of the composite integrated semiconductor device according an embodiment of to the present invention.

FIG. 5 is a perspective view showing the composite integrated semiconductor device according to an embodiment of the present invention as applied to a control unit for the electrical equipment of an automobile.

FIG. 6 is a plan view showing a Small Outline Package (SOP) for sealing the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 7 is a perspective view showing a Dual Inline Package (DIP) for sealing the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 8 is a plan view showing a Quad Flat Package (QFP) for sealing the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 9 is a plan view showing a Ball Grid Array (BGA) package or a Chip Size Package (CSP) for sealing the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 10 is a circuit diagram showing an example of the configuration of one of a plurality of units of the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 11 is a circuit diagram showing another example of the configuration of a unit of the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 12 is a circuit diagram showing another example of the configuration of a unit of the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 13 is a circuit diagram showing another example of the configuration of a unit of the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 14 is a circuit diagram showing another example of the configuration of a unit of the composite integrated semiconductor device according to an embodiment of the present invention.

FIG. 15 is a block diagram showing a configuration of a circuit block shown in FIG. 10 and FIG. 13.

FIG. 16 is a block diagram schematically showing an interface between a functional circuit comprising a plurality of conventional discrete semiconductor components and a semiconductor device.

FIG. 17 is a section view showing an example of an input/surge absorbing circuit according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a block diagram showing an example configuration of the composite integrated semiconductor device 15 according to an embodiment of the present invention. FIG. 2 is a block diagram schematically showing an example of an interface between the composite integrated semiconductor device 15 of FIG. 1 and another semiconductor device 4. As shown in FIG. 1 and FIG. 2, the composite integrated semiconductor device 15 is comprised of a plurality of integrated circuits 7. The integrated circuits 7 are connected in parallel between reference electric potentials formed in the same semiconductor substrate, and sealed in a semiconductor package 6.

Each integrated circuit 7 has a unit structure with a configuration including an input surge/noise absorbing circuit 8 absorbing surge or noise, an attenuating/level-shifting circuit 9 providing an attenuating or a level-shifting operation, and an electrical signal converting circuit 10 providing an electrical signal converting operation. A reference electric potential of the input surge/noise absorbing circuit 8 differs from a reference electric potential of the electrical signal converting circuit 10. Thus, the input surge/noise absorbing circuit 8 and the electrical signal converting circuit 10 are connected via the attenuating/level-shifting circuit 9.

Referring to FIG. 1 and FIG. 2, each input terminal 16 (i.e., inputting device) is projected from the semiconductor package 6. Each output terminal 17 (i.e., outputting device) is projected from another side of the semiconductor package 6. The input surge/noise absorbing circuit 8 of each unit 7 absorbs electrostatic surge or electromagnetic wave noise applied between an input terminal 16 and a grounding line 13, or between the grounding line 13 and a first power source line 11.

As shown in FIG. 2, an external electrical input signal 2 transmitted to each of the input terminals 16 of the composite integrated semiconductor device 15, to the input surge/noise absorbing circuit 8, and then to an input line 18 of the attenuating/level-shifting circuit 9. The attenuating circuit 9 carries out attenuation of a transient and DC voltage component of the electrical input signal 2. An electrical signal output from the attenuating circuit 9 is transmitted to an input line 19 of the electrical signal converting circuit 10.

The electrical signal converting circuit 10 converts the electrical signal from the attenuating circuit 9 to an electrical output signal 3 for which an applied voltage of a second power source line 12 to a grounding line 14 is a reference voltage. The electrical output signals 3 from each of the units 7 are output through the output terminals 17 of the composite integrated semiconductor device 15 and transmitted to the input terminals 5 of a semiconductor device 4, such as a microcomputer or a large-scale integrated (LSI) circuit.

FIG. 3 is a plan view of a chip showing an example of a chip layout of the composite integrated semiconductor device according to an embodiment of the invention. In the example of the semiconductor chip forming the composite integrated semiconductor device 15 of FIG. 3, an input surge/noise absorbing circuit 8, an attenuating circuit 9, and an electrical signal converting circuit 10 are aligned in the lateral direction of the chip (i.e., left-to-right direction in FIG. 3) to form an integrated circuit. The integrated circuits that are formed are aligned in the longitudinal direction of the chip (i.e., top-to-bottom direction in FIG. 3).

The chip layout of FIG. 3 shows two regions 20 and 22 aligned laterally at the bottom of FIG. 3. Region 20 is a ground for the input surge/noise absorbing circuits 8, and region 22 is a ground for the electrical signal converting circuits 10. Two regions 20 and 22 are formed because of a difference in respective reference electric potentials.

As shown in FIG. 4, each integrated circuit 7, which is a unit structure of the composite integrated semiconductor device 15, may be formed with only, for example, the input surge/noise absorbing circuit 8. Similarly, although not shown, each integrated circuit 7 may be formed with only the attenuating circuit 9, or only with the electrical signal converting circuit 10. Furthermore, each integrated circuit 7 may be formed with any two of the input surge/noise absorbing circuit 8, the attenuating circuit 9, and the electrical signal converting circuit 10.

FIG. 5 shows an example of applying the composite integrated semiconductor device according to an embodiment of the present invention to the electrical control unit (EDU) that controls the electrical equipment of an automobile, such as the engine, the automatic transmission, the anti-lock braking system, etc. In FIG. 5, the control unit 24 is drawn as being transparent so that the inner structure can be seen. In the control unit 24, the composite integrated semiconductor device 15 and a semiconductor device 4, which is a control device such as a microcomputer, are mounted on a printed circuit board 25. A connector 26 for the control unit 24 is also mounted on the printed circuit board 25.

Electrical input signals 2 are input from outside the control unit 24 to the connector 26. The semiconductor device 4 uses the electrical input signals 2 to gather information, to determine equipment status, etc. for the automobile. Therefore, the composite integrated semiconductor device 15 is positioned between the connector 26 and the semiconductor device 4. When a plurality of input signals 2 with electric potentials differing from one another are input to the composite integrated semiconductor device 15, resistors (not shown) are connected to the input terminals 16 of the composite integrated semiconductor device 15, with each of the input terminals 16 being matched to each of the input signals 2.

The connector 26 receives an electrostatic discharge pulse and electromagnetic interference noise. However, the composite integrated semiconductor device 15 removes the electrostatic discharge pulse and the electromagnetic interference noise. Then, electrical signals without the electrostatic discharge pulse and the electromagnetic interference noise are converted in the composite integrated semiconductor device 15 to signals (i.e., electrical output signals 3) having an adequate electric potential level for transmission to the input terminals of the semiconductor device 4. By using the composite integrated semiconductor device 15, as compared with the conventional configuration of FIG. 16, in which equivalent functions are provided using a plurality of discrete components, the mounting area of the semiconductor components 1 occupying the printed circuit board 25 is decreased, together with a reduction in the cost of mounting the semiconductor components.

When the composite integrated semiconductor device 15 according to an embodiment of the present invention is applied to the electrical equipment of an automobile, the composite integrated semiconductor device 15 is able to withstand electrostatic discharge pulses of approximately ±0.5 kV to 15 kV or more at approximately 150 pF and 500Ω in accordance with D001-94 of the Japan Automobile Standard Organization (JASO), or to withstand electrostatic discharge pulses of approximately ±1000V or more at 100 pF and approximately 1500Ω in accordance with standard ED-4701-1 of the Electronic Industries Association of Japan (EIAJ). Moreover, the composite integrated semiconductor device 15 is able to withstand electromagnetic interferences of approximately 20 to 100 V/m or more at approximately 10 kHz to 200 MHz.

Next, details are provided regarding the semiconductor package 6. FIG. 6 is a plan view showing an example of sealing the composite integrated semiconductor device 15 of an embodiment of the present invention in a Small Outline Package (SOP) 31. As shown in FIG. 6, a plurality of output terminals 34 are positioned about 180° from a plurality of input terminals 33, thereby preventing surge and noise applied to the input terminals 33 from being transmitted to the output terminals 34. In FIG. 6, arrows with reference numerals 32 and 35 represent the electrical input signals and the electrical output signals, respectively.

FIG. 7 is a perspective view showing an example of sealing the composite integrated semiconductor device 15 in a Dual In-Line Package (DIP) 36. As shown in FIG. 7, a plurality of output terminals 39 are positioned about 180° from a plurality of input terminals 38, thereby preventing surge and noise applied to the input terminals 38 from being transmitted to the output terminals 39. In FIG. 7, arrows with reference numerals 37 and 40 represent the electrical input signals and the electrical output signals, respectively.

FIG. 8 is a plan view showing an example of sealing the composite integrated semiconductor device 15 in a Quad Flat Package (QFP) 41. As shown in FIG. 8, a plurality of output terminals 44 are separated from a plurality of input terminals 43 in one or more different directions (two directions in the example shown in FIG. 8) by an angle of about 90° or more. In FIG. 8, arrows with reference numerals 42 and 45 represent the electrical input signals and the electrical output signals, respectively. Alternatively, one set of input or output terminals may protrude from a side of the semiconductor package 6 and the other set of terminals may protrude from the bottom of the semiconductor package 6.

FIG. 9 is a plan view showing an example of sealing the composite integrated semiconductor device 15 in a Ball Grid Array (BGA) package 46 or a Chip Size Package (CSP) 46. As shown in FIG. 9, a plurality of output terminals 49 are disposed on a side different from a side provided with a plurality of input terminals 48 by an angle of approximately 90° or more. In the example shown in FIG. 9, the output terminals 49 and the input terminals 48 are located on opposite sides of the composite integrated semiconductor device 15. In FIG. 9, reference numeral 47 denotes the electrical input signals and reference numeral 50 denotes the electrical output signals.

In the various examples of semiconductor packages 6 as described above, a plurality of the input terminals are collected together on one side of the semiconductor package 6 and a plurality of the output terminals are collected together on the other side. Any power source terminals and grounding terminals are located at the remaining sides. In addition, the semiconductor substrate on which all the semiconductor components are integrated may be sealed using a resin or ceramic.

FIG. 10 through FIG. 14 are circuit diagrams showing specific circuit configurations for the input surge/noise absorbing circuit 8, the attenuating circuit 9, and the electrical signal converting circuit 10. Each of FIGS. 10 through 14 shows one of the integrated circuits 7, which is a unit structure of the composite integrated semiconductor device 15. The electrical signal converting circuit 10 is not shown in FIGS. 11 and 12.

The example shown in FIG. 10 has ten diodes 51 to 60, six resistors 61 to 66, and a circuit block 10, which is the electrical signal converting circuit 10 (described below). The example shown in FIG. 11 has eight diodes 71 to 78 and five resistors 79 to 83. The example shown in FIG. 12 has eleven diodes 91 to 101, five resistors 102 to 106, and an operational amplifier 107. The example shown in FIG. 13 has nine diodes 111 to 119, six resistors 120 to 125, and an electrical signal converting circuit 10 (circuit block). The example shown in FIG. 14 has three diodes 131 to 133, two resistors 134 and 135, seven MOSFETs 136 to 142, and a capacitor 143. The circuit blocks 10 of FIGS. 10 and 13 are formed using conventional techniques and may include circuits such as an operational amplifier (OP amp) 151, a buffer 152, an inverter 153, a logic gate 154, a filter 155, and a ROM 156, as shown in FIG. 15.

The components of the circuits shown in FIGS. 10-14 are formed using conventional techniques. For example, the diodes 51 to 60, 71 to 78, 91 to 101, 111 to 119, and 131 to 133 may be formed, for example, using PN junction structures having a p-type diffused region and an n-type diffused region, or by MOSFETs having a main terminal and a gate that are short-circuited. The resistors 61 to 66, 79 to 83, 102 to 106, 120 to 125, 134, and 135 may be formed of, for example, diffused resistors having a diffused region formed in a semiconductor substrate, resistors formed of polysilicon, or well resistors having a well formed in a semiconductor substrate.

Furthermore, the capacitor 143 of FIG. 14 may be formed by, for example, a well with polysilicon layered thereon through an insulation layer. In addition, the OP amp 151, the buffer 152, the inverter 153, the logic gate 154, the filter 155, and the ROM 156 may be formed by MOSFETs, as well as by the above-described resistors and capacitors. Voltages at various parts of the circuits in FIGS. 10-13 are provided as approximately 24V at IN, 18V at Vcc1, 7V at Vcc2, and 4.0 to 5.3V at OUT.

FIG. 17 shows an example of an input/surge absorbing circuit according to an embodiment of the present invention. When a surge goes into a signal line, the surge flows through diode 51 and diode 52 to the ground GND. As such, a diode is provided between a power source V_(cc) and the ground and, therefore, a connected diode between the signal line and the ground is not needed. Therefore, if a surge voltage is applied between the signal input port and the ground, the surge current flows from the input port through diode 51 and diode 52 to the ground.

Furthermore, diode 51 and diode 52 are formed as vertical type semiconductor devices. This enables using an n-type semiconductor substrate and setting a potential of the semiconductor substrate to a power level of the power source. As a result, a cathode of diode 51 can be connected to a cathode of diode 52 in the semiconductor without the need for external wiring, such as bonding wires.

An n-type semiconductor substrate has uniform impurity concentration and is easily available. Therefore, diodes 51 and 52 can be formed by forming a p-region in the n-type semiconductor substrate having a uniform impurity concentration, resulting in diodes with few uneven characteristics in the same semiconductor substrate. As a result, surge absorbing circuits with high performance and uniform characteristics are provided.

Furthermore, the manufacturing process for such diodes requires the use of very few photomasks, such that manufacturing is relatively simple when compared with other lateral type semiconductor devices. In addition, there is no need for areas on the surface of the semiconductor substrate for external wire bonding because cathodes of both diodes 51 and 52 can be connected in the semiconductor, such that the surge absorbing circuit can be manufactured on a small area of the substrate. This is especially important when a plurality of surge absorbing circuits is formed on the same substrate. Alternatively, diode 51 and diode 52 may be formed as lateral type semiconductor devices.

According to various aspects for embodiments of the present invention as described above, the input surge/noise absorbing circuit 8, the attenuating circuit 9, and the electrical signal converting circuit 10 are integrated in the same semiconductor substrate. Thus, the number of components mounted on a printed circuit board is reduced compared with a conventional circuit configuration in which semiconductor devices are formed by combining a plurality of discrete components. As a result, the mounting area on the printed circuit board and the number of man-hours required to mount the components are reduced.

The present invention is not limited to the above described aspects, but may be modified, provided the circuits at stages preceding a microcomputer, such as the circuit for absorbing noise and surge and the circuit for making electric signal levels match those of the microcomputer, are integrated in the same semiconductor substrate.

The many features and advantages of the invention are apparent from the detailed specification and, thus, it is intended by the appended claims to cover all such features and advantages of the invention that fall within the true spirit and scope of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. 

1. A composite integrated semiconductor device, comprising: inputting means for inputting an input electrical signal; outputting means for outputting an output electrical signal; input surge/noise absorbing means for absorbing surge or noise of the input electrical signal, and being connected between the inputting means and the outputting means, the input surge/noise absorbing means including a first diode being connected between a power source line and the inputting means and a second diode being connected between the power source line and a ground; and attenuating circuits attenuating the input electrical signal, and being connected between the inputting means and the outputting means, wherein a plurality of integrated circuits are formed, each of the plurality of integrated circuits including an input surge/noise absorbing means and an attenuating circuit, and each of the plurality of integrated circuits is integrated in an n type semiconductor substrate, the input surge/noise absorbing means includes at least two vertical type diodes, an anode of one of the at least two vertical type diodes being connected to the inputting means, and an anode of another of one of the at least two vertical type diodes being connected to the ground, and the n type semiconductor substrate is connected to the power source line.
 2. The composite integrated semiconductor device as claimed in claim 1, wherein the input surge/noise absorbing means is able to withstand an electrostatic discharge capability of approximately ±0.5 kV to 15 kV at approximately 150 pF and 500Ω.
 3. The composite integrated semiconductor device as claimed in claim 1, wherein the input surge/noise absorbing means is able to withstand an electrostatic discharge capability of approximately ±1000V at approximately 100 pF and 1500Ω.
 4. The composite integrated semiconductor device as claimed in claim 1, wherein the input surge/noise absorbing means is able to withstand an electromagnetic compatibility capability of approximately 20 to 100 V/m at approximately 10 kHz to 200 MHz.
 5. The composite integrated semiconductor device as claimed in claim 1, wherein the outputting means is positioned at an angle of about 90 degrees or more with respect to a position of the inputting means.
 6. A composite integrated semiconductor device, comprising: inputting means for inputting an input electrical signal; outputting means for outputting an output electrical signal; input surge/noise absorbing means for absorbing surge or noise of the input electrical signal, and being connected between the inputting means and the outputting means, the input surge/noise absorbing means including a first diode being connected between a power source line and the inputting means and a second diode being connected between the power source line and a ground; attenuating circuits attenuating the input electrical signal, and being connected between the inputting means and the outputting means; and electrical signal converting means for converting the input electrical signal to the output electrical signal, and being connected between the inputting means and the outputting means, wherein a plurality of integrated circuits are formed, each of the plurality of integrated circuits including an input surge/noise absorbing means and an attenuating circuit, and each of the plurality of integrated circuits is integrated in an n type semiconductor substrate, the surge/noise absorbing means, attenuating circuits and electrical signal converting means are connected in sequence toward the outputting means from the inputting means between the inputting means and the outputting means, the plurality of input surge/noise absorbing means includes at least two vertical type diodes, an anode of one of the at least two vertical type diodes being connected to the inputting means, and an anode of another of one of the at least two vertical type diodes being connected to the ground, and the n type semiconductor substrate is connected to the power source line.
 7. The composite integrated semiconductor device as claimed in claim 6, wherein the input surge/noise absorbing means is able to withstand an electrostatic discharge capability of approximately ±0.5 kV to 15 kV at approximately 150 pF and 500Ω.
 8. The composite integrated semiconductor device as claimed in claim 6, wherein the input surge/noise absorbing means is able to withstand an electrostatic discharge capability of approximately ±1000V at approximately 100 pF and 1500Ω.
 9. The composite integrated semiconductor device as claimed in claim 6, wherein the input surge/noise absorbing means is able to withstand an electromagnetic compatibility capability of approximately 20 to 100 V/m at approximately 10 kHz to 200 MHz.
 10. The composite integrated semiconductor device as claimed in claim 6, wherein the outputting means is positioned at an angle of about 90 degrees or more with respect to a position of the inputting means.
 11. A composite integrated semiconductor device, comprising: a plurality of inputting devices receiving an input electrical signal; a plurality of outputting devices transmitting an output electrical signal; a plurality of input surge/noise absorbing circuits to absorb surge or noise of the input electrical signal, each of the input surge/noise absorbing circuits being connected between respective ones of the inputting devices and corresponding outputting devices, each of the input surge/noise absorbing circuits including a first diode being connected between a power source line and the inputting device and a second diode being connected between the power source line and a ground, respectively; a plurality of attenuating circuits to attenuate the input electrical signal, each of the attenuating circuits being connected between respective ones of the inputting devices and corresponding outputting devices; and a plurality of an integrated circuits comprising the input surge/noise absorbing circuits and the attenuating circuits, and being integrated in a n type semiconductor substrate, wherein the plurality of input surge/noise absorbing circuits include at least two vertical type diodes, an anode of one of the at least two vertical type diodes being connected to an inputting device, and an anode of another of one of the at least two vertical type diodes being connected to the ground, and the n type semiconductor substrate is connected to the power source line.
 12. The composite integrated semiconductor device as claimed in claim 11, wherein each input surge/noise absorbing circuit is able to withstand an electrostatic discharge capability of approximately ±0.5 kV to 15 kV at approximately 150 pF and 500Ω.
 13. The composite integrated semiconductor device as claimed in claim 11, wherein each input surge/noise absorbing circuit is able to withstand an electrostatic discharge capability of approximately ±1000V at approximately 100 pF and 1500Ω.
 14. The composite integrated semiconductor device as claimed in claim 11, wherein each input surge/noise absorbing circuit is able to withstand an electromagnetic compatibility capability of approximately 20 to 100 V/m at approximately 10 kHz to 200 MHz.
 15. The composite integrated semiconductor device as claimed in claim 11, wherein the outputting devices are positioned at an angle of about 90 degrees or more with respect to a position of the inputting devices.
 16. A composite integrated semiconductor device, comprising: a plurality of inputting devices receiving an input electrical signal; a plurality of outputting devices transmitting an output electrical signal; a plurality of input surge/noise absorbing circuits to absorb surge or noise of the input electrical signal, each of the input surge/noise absorbing circuits being connected between respective ones of the inputting devices and corresponding outputting devices each of the input surge/noise absorbing circuits including a first diode being connected between a power source line and the inputting device and a second diode being connected between the power source line and a ground, respectively; a plurality of attenuating circuits to attenuate the input electrical signal, each of the attenuating circuits being connected between respective ones of the inputting devices and corresponding outputting devices; a plurality of electrical signal converting circuits to convert the input electrical signal to the output electrical signal, each of the electrical signal converting circuits being connected between respective ones of the inputting devices and corresponding outputting devices; and a plurality of an integrated circuits comprising the input surge/noise absorbing circuits, the attenuating circuits, and the electrical signal converting circuits, and being integrated in a n type semiconductor substrate, wherein the surge/noise absorbing circuits, the attenuating circuits and electrical signal converting circuits are connected in sequence toward the outputting devices from the inputting devices between the inputting devices and the outputting devices, the plurality of input surge/noise absorbing circuits include at least two vertical type diodes, an anode of one of the at least two vertical type diodes being connected to an inputting device, and an anode of another of one of the at least two vertical type diodes being connected to the ground, and the n type semiconductor substrate is connected to the power source line.
 17. The composite integrated semiconductor device as claimed in claim 16, wherein each input surge/noise absorbing circuit is able to withstand an electrostatic discharge capability of approximately ±0.5 kV to 15 kV at approximately 150 pF and 500Ω.
 18. The composite integrated semiconductor device as claimed in claim 16, wherein each input surge/noise absorbing circuit is able to withstand an electrostatic discharge capability of approximately ±1000 V at approximately 100 pF and 1500Ω.
 19. The composite integrated semiconductor device as claimed in claim 16, wherein each input surge/noise absorbing circuit is able to withstand an electromagnetic compatibility capability of 20 to 100 V/m at approximately 10 kHz to 200 MHz.
 20. The composite integrated semiconductor device as claimed in claim 16, wherein the outputting devices are positioned at an angle of about 90 degrees or more with respect to a position of the inputting devices. 